How can a high positively influence the performance of a jazz musician? The effect cited most often as an answer is the altered sense of time during a high. Dr. James Munch, pharmacologist and associate of drug czar and infamous marijuana prohibitionist Harry J. Anslinger during the 30s and 40s, produced many ridiculous claims about the alleged horrible effects of marijuana.
I never sing a song the same way twice”
Billie Holiday (1915-59)
Jazz is about being in the moment”
How can a high positively influence the performance of a jazz musician? The effect cited most often as an answer is the altered sense of time during a high. Dr. James Munch, pharmacologist and associate of drug czar and infamous marijuana prohibitionist Harry J. Anslinger during the 30s and 40s, produced many ridiculous claims about the alleged horrible effects of marijuana, but expressed this point crisp clear years later, when he said about marijuana using musicians:
“(…) the chief effect as far as they were concerned was that it lengthens the sense of time, and therefore they could get more grace beats into their music than they could if they simply followed the written copy. (…) if you are using marijuana, you are going to work in about twice as much music between the first note and the second note. That’s what made jazz musicians.”
Hyperfocussing, Mind Racing, and an Altered Sense of Time
Munch’s point about the altered sense of time and its role in jazz music is important; however, this is only one of several crucial effects of marijuana which can play a positive role for jazz performers.
One of the fundamental effects of marijuana is to hyperfocus attention. Mezzrow remembers this hyperfocus for his auditory experience when he first got high:
“The first thing I noticed was that I began to hear my saxophone a though it was inside my head, but I couldn’t hear much of the band in back of me, although I knew they were there. All the other instruments sounded like they were far off in distance;(…)”. 
This hyperfocus allows him to better concentrate on his immediate tactile sensation of his instrument, which improves his control:
”Then I began to feel the vibrations of the reed much more pronounced against my lip (…) I found I was slurring much better and putting just the right feeling into the phrase.” 
During a high, this hyperfocus of attention allows not only for a more analytic perception of whatever comes into this focus; it might also lead to mindracing, another effect often described by marijuana users probably related to the prolonged sense of time mentioned above..
In his 1938 report “Marihuana, America’s New Drug Problem”, Walton states:
“The exaggeration of the sense of time is one of the most conspicuous effects. It is probably related to the rapid succession of ideas and impressions which cross the field of consciousness.”
The acceleration of thought processes is sometimes experienced as a stream of associatively connected thoughts, memories, or imaginations, which also depends on the consumed dosage. Obviously, the speeding up of mental processes in a narrowed down tunnel of attention can help a musician to more rapidly play an improvised solo, or to keep up with the speed of others. If we want to better understand what happens during such an accelerated stream of thought during a high we have to look at some other related effects of marijuana.
Short Term Memory Disruptions, Enhanced Pattern Recognition & Imagination
With their mind unusually focussed on the present moment or thought, marijuana users sometimes forget about the beginning of a thought chain or about the original “frame” of the discourse. This often leads to a “what-were we-talking-about?”- moment; they are loosing the thread. While this is often only negatively described in the scientific literature on marijuana as “short-term memory disruptions”, it can also have positive aspects. While inexperienced users – especially when using high dosages – become disoriented, skilled users using good quality marijuana can keep the thread, but feel that their stream of thought is less constrained by the original theme or frame, and less constrained by the goal it was intended to go towards. This allows a stream of thoughts or imaginations to ‘jump’ more freely along unusually wide associations.
Many marijuana users have also reported an enhanced ability to see new patterns during a high. They find new similarities between various patterns. In a musical performance, these effects can then lead to a rapid improvisation over known musical themes, which loosely associate them to new patterns and ideas or they lead to new connections or transitions between musical themes. Subjectively, this leads to the feeling of a rapid and effortless flow of ideas.
Marijuana users have also described that a high enhances their imaginative abilities – visually, auditory, gustatory, or otherwise – a capacity which is crucial to the invention of new ideas. Needless to say how important an enhanced ability for auditory imagination can be for a musical performer coming up with a new improvisation on stage, or for a composer working on a new song.
In Mezzrow’s first high, the interrelated effects of mind-racing, a hyperfocus of attention, an enhanced pattern recognition ability and an enhanced imagination lead to an explosive performance:
”All the notes came easing out of my horn like they’d already been made up, greased and stuffed into the bell, so all I had to do was to blow a little and send them on their way, one right after the other, never missing, never behind time, all without an ounce of effort. The phrases seem to have continuity to them and I was sticking to the theme without ever going tangent. I felt I could go on playing for years without running out of ideas and energy”.
The Aphrodisiac Effect of Marijuana
Mezzrow mentions another way in which marijuana affected jazz:
“Us vipers began to know that we had a gang of things in common: (…) we all decided that the muta had some aphrodisiac qualities too, which didn’t run us away from it.”
Many have cited Mezzrow’s passages above to illustrate the influence of marijuana on jazz, but they never mention that his high adventure on stage ends in an ecstatic group experience like decades later at concerts of the Beatles:
“The people were going crazy over the subtle changes in our playing; (…) some kind of electricity was crackling in the air and it made them all glow and jump. (…) it seemed like all the people on the dance floor were melted down into one solid, mesmerized mass; (…) looking up at the band with hypnotic eyes and swaying (…). An entertainer (..) was throwing herself around like a snake with the hives. The rhythm really had this queen; (…) what she was doing with (..) her anatomy isn’t discussed in mixed company. “Don’t do that!” she yelled. “Don’t do that to me!”
That’s probably what Duke Ellington meant when he said about jazz:
“By and large, jazz has always been like the kind of a man you wouldn’t want your daughter to associate with.”
(to be continued in part III)
 Larry “Ratso” Sloman (1998), Reefer Madness. The History of Marijuana in America, pp. 146-147.
 Mezz Mezzrow (1946/1990), Really the Blues, Souvenir Press, London, p. 72.
 Compare Sebastian Marincolo (2010) High. Insights on Marijuana, Chapter 6, “Intensified Imagination, Mindracing, and Time Perception Distortions”, Dog Ear Publishing, Indiana.
 Walton, R.P. (1938), Marijuana. America’s New Drug Problem, Philadelphia, Lippincott, S.105.
 Compare Andrew Weil (2004). The Natural Mind: A New Way of Looking
at Drugs and the Higher Consciousness. Houghton Mifflin, Boston.
 Mezz Mezzrow (1946/1990), Really the Blues, Souvenir Press, London, p. 93.
 ibid, p. 73.